Automatic shut-off device for oil burners



July 27,1926. 1,593,818

R. L. DORAN AUTQMXTIIC SHUT-OFF DEVICE FOR 011. BURNERS Filed 001;. 14,1925 3 Sheets-Sheet 1 Pakzi 520mm 3V f I a 3 July 27 1926.

. 1,593,818 R. L. DORAN AUTOMATIC SHUT-OFF DEVICE FOR OIL BURNERS FiledOct. 14 1925 3 Sheets-Sheet 2 wkw July 27,1926. 1,593,818

R. L. DORAN AUTOMATIC SHUT-0FF DEVICE FOR OIL BURNERS Filed ()Qkn l41925 3 ShBBtS-Shflt 3 llllll fizz/7W 2056; J 7? Patented July 27, 1926.

UNITED STATES ROBERT L. DURAN, OF CHICAGO, ILLINOIS.

AUTOMATIC SHUT-OFF DEVICE FOR OIL BURNERS.

Application filed October 14, 1925. Serial No. 62,420.

This inventionrelates to improvements in oil furnaces, more particularlyto safety shut-off devices for the same and especially for such devicesoperable by an accumulation of unburned fuel.

The chief characteristics are a tilting lever having a receptacle intowhich the oil is drained from the burner and having a mercury positionoperated motor switch device mounted thereon, a weight adapted to berotatedinto disengagement with a sup-- porting pin by the said lever,and a weighted shutbff valve. This valve being normally propped open bya projection on a trigger lever which is moved to allow the valve toclose by the falling weight when a small amount of oil has collected inthe lever receptacle to release the weight by tilting the lever. Theinvention also includes special means for safeguarding against brokensprings.

I-Ieretofore safety shut-offs have been operatedby a weight released byan accumulation'of unburned oil in which spring pressed supports werereleased for withdrawal from supporting the weight, and other likemethods which required considerable power to operate and usually theshut-oil" was accomplished by allowing the main control valve of thedeviceto move to closed pos1t10n.

The main objects of this invention are to provide an automatic shut-offwhich is more sensitive and positive in its operation, which requiresless power to release the motor element, which may function entirelyindependent of all springs, which is simple and substantial in itsconstruction, which is readily operation mechanism.

Fig. 2 is a plan View of a portion of Figure 1.

Fig. 3 is taken on line 33 of Figure 1.

Fig. l is a larger scale section of the valve taken on line 4lof Fig. 2with the outlet connection shown as if located in the same I plane, withthe valve in closed position.

Figure 5 is a fragmental view showing the relation between the end ofthe trigger and the lower end of the plunger, shown in the lower part ofFigure 4 and other figures.

Fig. 6 is a view similar to Fig. 5 showing the same parts in the normalposition with the shut-off valve held open.

Fig. 7 is a section on line 77 of Fig. 3. Fig. 8 is a section on line8-8 of Fig. 3. Fig. 9 is a section on line 99 of Fig. 3. As shown in thedrawings the shut-off device 10 is insertedin the oil supply line 11ahead of the usual control valve which is mounted in the housing 12 fromwhich the oil passes through the pipe 13 to the burner which is notshown, but could be like the v burner shown in my Patent No. 1,559,559,

16 and collects in the bucket or receptacle- 17 which is suspended fromone arm of the pivoted lever 18.

The lever 18 1s pivoted on the frame member 19 which is attached to thebase frame 20 supported by the standard 21, and

' which passes freely through the groove 28.

Then lever 18 is rotated so that the crank pin 22 is in line with thestop pin 26, whereupon the weight is raised above the stop pin 26 androtated so that the weight rests on the stop 26 with the crank pin 22engaged in the slot. With the bucket 17 empty the friction of the weighton the stop 26 holds the arm 18 in the corresponding set position inwhich the lever 18 is closely balanced by means of the weight 27 whichis held in position on the weight arm 28 between the threaded nuts 29.

When oil collects in the bucket 17, the arm 18 rotates and,through thecrank pin 1 should not-be sufiicient to hold. the trigger -.30 'as.et,'i'a safetyngravity ioperated latch 43..."

is provided. Theilatch48 is pivotally suslower end of the connection,turns the weight until the slot 23 registers with the pin 26 andreleases the weight.

In falling, the weight strikes the trigger lever 30 which has one endpositioned in the path of the weight and is pivotally mounted on theyoke 31 which is secured to the valve housing 32 of the shut-oft 10.

The housing 32 is provided with a transverse partition 33 forming upperand lower chambers which are connected by the valve passage 34,centrally located in 33. The valve 35 is vertically guided in the upperchamber by the periphery of the valve weight 36 which is secured to thestem of the valve 35 and in which is seated a valve closing spring 37hearing against the top plate 38. Since the oil is admitted into theupper chamber through the supply pipe 11, the effective oil pressure onthe area of the passage 34 together with the weight and the spring urgethe valve 35 downwardly to close the passage 34, to the shut-ofiposition shown in Fig. 4.

Normally the valve 35 is propped open by lifting the trigger lever 30 sothat the ball 39, carried by 30, raises the plunger 40 which engages inthe shallow recess in the chamlered nut 41 locked on the lower end ofthe plunger 40. The plunger is guided in the member 31 and stopped fromfalling through by the flange portion 42. In the released position theupper end of 40 clears the diaphragm nut 43, secured in the diaphragm 44which closes the end of the lower chamher; and inner end of the nut 43clears the rojection 45 of the valve 35 thus allowing t e valve to seat.

\Vhen the plunger 40 is raised. the contacts are made and the valve isheld up to open the passage 34 to the lower chamber and allowthe oil toflow through the passage 46 and through the pipe 47 into the controlvalve housing 12 which regulates the oil flow to the burner.

As mentioned above and shown in Fig. 6, the ball 39 engages in the lowerend of the plunger member 41 and since pressure is being exerteddownwardly by the weight 36 and the spring 37, the lever 30 is therebyheld in set position. In case the spring 37 should fail and the loadofzthe weight 36 :t' ipended i r'omitheuframexlt) and :has a finger 449gwhich tund'eizlies the projection 50- ofthe "trigger lever'f30. I

When the *weightt-.:24 falls it strikes the projecting portion orthe'latch 4OJ-and throws the finger 49 out of the way ."bQ I OIGDStP-lk-u;mg the lever 30, which is? struck-:with a i i for'o'e suflici-ent it'o"overcome the restrainingmovement of the ball engagement and release thevalve 35 for closing.

When the lever 18 is rotated to release the weight 24, the supplycircuit of the motor 15 is also opened by means of the mercury switch51. The switch 51 is mounted on the weight arm of the lever 18 in tiltedposition so that when the lever is set the motor circuit leads 52 areconnected and when the lever is rotated to oii position the connectionis broken.

\Vhile but one illustrative embodiment has been shown many omissions andalterations may be made without departing from the spirit of theinvention.

I claim 1. A construction of the class described having an oil supplyvalve, a safety shutoff comprising,-a stop, a slidably mounted weightnormally rotated to rest on said stop and adapted on being released toclose the valve, and means operable by an accumulation of unburned fuelfor rotating said weight relative to the stop for releasing the samefrom the stop.

2. In a construction of the class described, valve operating meanscomprising a stop, a slidably mounted weight adapted to operate thevalve having projecting portions and adapted to be rotated to engage theprojecting portions with the stop for holding the weight in inoperativeposition, and means for rotating the weight to disengaged position forreleasing for operating the valve.

In a construction of the class described, a valve having an operatinglever and a stop, a weight suspended over the lever and held by beingrotated into engagement with said stop, and means for rotating theweight for disengagement with the stop thereby allowing the weight tofall onto the said lever to operate the valve.

4. In combination in an oil furnace, an automatically closing valve,means normally holding the valve open having an operating lever, a stopmember, a Weight slidably mounted on the lever and held by projectingportions of the weight being rotated into engagement with said stopmember, and means for rotating the weight to move said projectingportions out of engagement with the stop thereby releasing the Weight toimpinge the lever to release and, allow the valve to close. j

5. In combination inanoil furnace, an automatically closingva-lve, meansnormally holding the valve openihaving-anoperating lever, a stopmember,- :a-uweight. slidably mounted on the lever and held byprojecting'portions of the Weight being rotated into. engagement withsaid stop member, and means operablepby; an accumulation of unburnedfuel-forrot'ating the weight toimove said projecting portions 101112.of: engagement with the/stop .thereby/releasing thetweight to impingethe lever to release and allow the valve to close.

6. 1n a construction of the class described having a shut-off valve,releasable means for operating said valve comprising a stop, a Weightslidably guided in relation to the stop and having a groove in the edgeadapted to register With the stop, a pivoted balance arm having a crankpin engaging in said groove for rotating the Weight when in positionabove the stop, and means operable by an accumulation of unburned fuelfor rotating said balance arm.

7. In combination in an oil furnace a gravity-closed shut-off valve, atrigger for propping the valve open, and a Weight releasable by anaccumulation of unburned fuel for dislodging the trigger to allow thevalve to close, and a latch operable by the released Weight normallyretaining the trigger in set position.

8. In combination in an oil furnace, an automatically closing valve, atrigger member adapted to be set to hold the valve open, a stop, aslidable Weight having outstanding portions adapted to be rotated intoengagement with the stop, a balance lever having a crank pin in slidableengagement with the Weight adapted to rotate said portions out ofengagement With said stop, and means for moving the balance lever.

Signed at Chicago this 12th day of October, 1925.

ROBERT L. DURAN,

